Driving a motor vehicle in modern traffic conditions is a very complicated and dangerous task. The driver must be aware of all oncoming road hazards and traffic control devices including stopped cars and red lights. Highway driving poses the ultimately dangerous task of watching oncoming road hazards while at the same time looking backwards. It is necessary to look both sideways and backwards before safely changing lanes on a highway. A failure to properly look both sideways and backwards before changing lanes can lead to serious high speed accidents. Such accidents often cause serious bodily harm or death.
Rearview mirrors located both inside the windshield and on the sides of vehicles so far have been the only widely accepted means for detecting vehicles on the sides or behind the driver's vehicle. All such rear view mirrors known to the applicant leave at least one blind spot where the driver cannot detect a nearby vehicle. These blind spots generally exist right next to the rear fenders of a car or next to the rear wheels of a truck. Sometimes an entire car or motorcycle can be driving right alongside the driver's car totally undetectable by the driver even after checking his rear view mirrors. Various range detecting technologies have been applied to motor vehicles to assist a driver to control his vehicle.
U.S. Pat. No. 3,152,317 discloses a following vehicle distance sensing means using rearward facing lamps on the lead vehicle and a forward facing light angle detector on the following vehicle. A circuit computes the distance from the varying angles of convergence of the two rearward facing lamps.
U.S. Pat. No. 3,942,601 discloses a personnel proximity detection system for trucks having hazardous machinery on the outside. Photoelectric or ultrasound or capacitance antenna means are used to trigger safety shut-offs when a person is too close to the machinery.
U.S. Pat. No. 4,232,286 discloses an electronic sensor on a vehicle which is used to indicate when a metal pipe imbedded in a rubber bumper moves closer to the vehicle.
U.S. Pat. No. 4,407,388 discloses a dual sensing system on a truck while reversing with means to stop the truck when a hazard is sensed. A radar and an infra red detector are used.
None of these devices is designed to mount at the rear of a car or truck and provide the driver with a dependable means to detect a vehicle right alongside in the driver's blind spot.